mtd, ubi, ubifs: resync with Linux-3.14

resync ubi subsystem with linux:

commit 455c6fdbd219161bd09b1165f11699d6d73de11c
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sun Mar 30 20:40:15 2014 -0700

    Linux 3.14

A nice side effect of this, is we introduce UBI Fastmap support
to U-Boot.

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Tom Rini <trini@ti.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Sergey Lapin <slapin@ossfans.org>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Joerg Krause <jkrause@posteo.de>

1 files changed, 455 insertions, 60 deletions

diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 146ce11eb1..d20b8578e7 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -1,35 +1,50 @@
 /*
  * Simple MTD partitioning layer
  *
- * (C) 2000 Nicolas Pitre <nico@cam.org>
+ * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
+ * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
+ * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
  *
- * This code is GPL
+ * SPDX-License-Identifier:	GPL-2.0+
  *
- * 	02-21-2002	Thomas Gleixner <gleixner@autronix.de>
- *			added support for read_oob, write_oob
  */
 
+#define __UBOOT__
+#ifndef __UBOOT__
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/kmod.h>
+#endif
+
 #include <common.h>
 #include <malloc.h>
 #include <asm/errno.h>
+#include <linux/compat.h>
+#include <ubi_uboot.h>
 
-#include <linux/types.h>
-#include <linux/list.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
-#include <linux/compat.h>
+#include <linux/err.h>
+
+#include "mtdcore.h"
 
 /* Our partition linked list */
-struct list_head mtd_partitions;
+static LIST_HEAD(mtd_partitions);
+#ifndef __UBOOT__
+static DEFINE_MUTEX(mtd_partitions_mutex);
+#else
+DEFINE_MUTEX(mtd_partitions_mutex);
+#endif
 
 /* Our partition node structure */
 struct mtd_part {
 	struct mtd_info mtd;
 	struct mtd_info *master;
 	uint64_t offset;
-	int index;
 	struct list_head list;
-	int registered;
 };
 
 /*
@@ -39,6 +54,30 @@ struct mtd_part {
 #define PART(x)  ((struct mtd_part *)(x))
 
 
+#ifdef __UBOOT__
+/* from mm/util.c */
+
+/**
+ * kstrdup - allocate space for and copy an existing string
+ * @s: the string to duplicate
+ * @gfp: the GFP mask used in the kmalloc() call when allocating memory
+ */
+char *kstrdup(const char *s, gfp_t gfp)
+{
+	size_t len;
+	char *buf;
+
+	if (!s)
+		return NULL;
+
+	len = strlen(s) + 1;
+	buf = kmalloc(len, gfp);
+	if (buf)
+		memcpy(buf, s, len);
+	return buf;
+}
+#endif
+
 /*
  * MTD methods which simply translate the effective address and pass through
  * to the _real_ device.
@@ -52,7 +91,8 @@ static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
 	int res;
 
 	stats = part->master->ecc_stats;
-	res = mtd_read(part->master, from + part->offset, len, retlen, buf);
+	res = part->master->_read(part->master, from + part->offset, len,
+				  retlen, buf);
 	if (unlikely(mtd_is_eccerr(res)))
 		mtd->ecc_stats.failed +=
 			part->master->ecc_stats.failed - stats.failed;
@@ -62,6 +102,36 @@ static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
 	return res;
 }
 
+#ifndef __UBOOT__
+static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
+		size_t *retlen, void **virt, resource_size_t *phys)
+{
+	struct mtd_part *part = PART(mtd);
+
+	return part->master->_point(part->master, from + part->offset, len,
+				    retlen, virt, phys);
+}
+
+static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
+{
+	struct mtd_part *part = PART(mtd);
+
+	return part->master->_unpoint(part->master, from + part->offset, len);
+}
+#endif
+
+static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
+					    unsigned long len,
+					    unsigned long offset,
+					    unsigned long flags)
+{
+	struct mtd_part *part = PART(mtd);
+
+	offset += part->offset;
+	return part->master->_get_unmapped_area(part->master, len, offset,
+						flags);
+}
+
 static int part_read_oob(struct mtd_info *mtd, loff_t from,
 		struct mtd_oob_ops *ops)
 {
@@ -72,8 +142,25 @@ static int part_read_oob(struct mtd_info *mtd, loff_t from,
 		return -EINVAL;
 	if (ops->datbuf && from + ops->len > mtd->size)
 		return -EINVAL;
-	res = mtd_read_oob(part->master, from + part->offset, ops);
 
+	/*
+	 * If OOB is also requested, make sure that we do not read past the end
+	 * of this partition.
+	 */
+	if (ops->oobbuf) {
+		size_t len, pages;
+
+		if (ops->mode == MTD_OPS_AUTO_OOB)
+			len = mtd->oobavail;
+		else
+			len = mtd->oobsize;
+		pages = mtd_div_by_ws(mtd->size, mtd);
+		pages -= mtd_div_by_ws(from, mtd);
+		if (ops->ooboffs + ops->ooblen > pages * len)
+			return -EINVAL;
+	}
+
+	res = part->master->_read_oob(part->master, from + part->offset, ops);
 	if (unlikely(res)) {
 		if (mtd_is_bitflip(res))
 			mtd->ecc_stats.corrected++;
@@ -87,35 +174,46 @@ static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 		size_t len, size_t *retlen, u_char *buf)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_read_user_prot_reg(part->master, from, len, retlen, buf);
+	return part->master->_read_user_prot_reg(part->master, from, len,
+						 retlen, buf);
 }
 
 static int part_get_user_prot_info(struct mtd_info *mtd,
 		struct otp_info *buf, size_t len)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_get_user_prot_info(part->master, buf, len);
+	return part->master->_get_user_prot_info(part->master, buf, len);
 }
 
 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 		size_t len, size_t *retlen, u_char *buf)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_read_fact_prot_reg(part->master, from, len, retlen, buf);
+	return part->master->_read_fact_prot_reg(part->master, from, len,
+						 retlen, buf);
 }
 
 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
 		size_t len)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_get_fact_prot_info(part->master, buf, len);
+	return part->master->_get_fact_prot_info(part->master, buf, len);
 }
 
 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 		size_t *retlen, const u_char *buf)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_write(part->master, to + part->offset, len, retlen, buf);
+	return part->master->_write(part->master, to + part->offset, len,
+				    retlen, buf);
+}
+
+static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
+		size_t *retlen, const u_char *buf)
+{
+	struct mtd_part *part = PART(mtd);
+	return part->master->_panic_write(part->master, to + part->offset, len,
+					  retlen, buf);
 }
 
 static int part_write_oob(struct mtd_info *mtd, loff_t to,
@@ -127,30 +225,41 @@ static int part_write_oob(struct mtd_info *mtd, loff_t to,
 		return -EINVAL;
 	if (ops->datbuf && to + ops->len > mtd->size)
 		return -EINVAL;
-	return mtd_write_oob(part->master, to + part->offset, ops);
+	return part->master->_write_oob(part->master, to + part->offset, ops);
 }
 
 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 		size_t len, size_t *retlen, u_char *buf)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_write_user_prot_reg(part->master, from, len, retlen, buf);
+	return part->master->_write_user_prot_reg(part->master, from, len,
+						  retlen, buf);
 }
 
 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 		size_t len)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_lock_user_prot_reg(part->master, from, len);
+	return part->master->_lock_user_prot_reg(part->master, from, len);
 }
 
+#ifndef __UBOOT__
+static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
+		unsigned long count, loff_t to, size_t *retlen)
+{
+	struct mtd_part *part = PART(mtd);
+	return part->master->_writev(part->master, vecs, count,
+				     to + part->offset, retlen);
+}
+#endif
+
 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 {
 	struct mtd_part *part = PART(mtd);
 	int ret;
 
 	instr->addr += part->offset;
-	ret = mtd_erase(part->master, instr);
+	ret = part->master->_erase(part->master, instr);
 	if (ret) {
 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 			instr->fail_addr -= part->offset;
@@ -171,30 +280,51 @@ void mtd_erase_callback(struct erase_info *instr)
 	if (instr->callback)
 		instr->callback(instr);
 }
+EXPORT_SYMBOL_GPL(mtd_erase_callback);
 
 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_lock(part->master, ofs + part->offset, len);
+	return part->master->_lock(part->master, ofs + part->offset, len);
 }
 
 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 {
 	struct mtd_part *part = PART(mtd);
-	return mtd_unlock(part->master, ofs + part->offset, len);
+	return part->master->_unlock(part->master, ofs + part->offset, len);
+}
+
+static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+	struct mtd_part *part = PART(mtd);
+	return part->master->_is_locked(part->master, ofs + part->offset, len);
 }
 
 static void part_sync(struct mtd_info *mtd)
 {
 	struct mtd_part *part = PART(mtd);
-	mtd_sync(part->master);
+	part->master->_sync(part->master);
 }
 
+#ifndef __UBOOT__
+static int part_suspend(struct mtd_info *mtd)
+{
+	struct mtd_part *part = PART(mtd);
+	return part->master->_suspend(part->master);
+}
+
+static void part_resume(struct mtd_info *mtd)
+{
+	struct mtd_part *part = PART(mtd);
+	part->master->_resume(part->master);
+}
+#endif
+
 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 {
 	struct mtd_part *part = PART(mtd);
 	ofs += part->offset;
-	return mtd_block_isbad(part->master, ofs);
+	return part->master->_block_isbad(part->master, ofs);
 }
 
 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
@@ -203,12 +333,18 @@ static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 	int res;
 
 	ofs += part->offset;
-	res = mtd_block_markbad(part->master, ofs);
+	res = part->master->_block_markbad(part->master, ofs);
 	if (!res)
 		mtd->ecc_stats.badblocks++;
 	return res;
 }
 
+static inline void free_partition(struct mtd_part *p)
+{
+	kfree(p->mtd.name);
+	kfree(p);
+}
+
 /*
  * This function unregisters and destroy all slave MTD objects which are
  * attached to the given master MTD object.
@@ -217,49 +353,78 @@ static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 int del_mtd_partitions(struct mtd_info *master)
 {
 	struct mtd_part *slave, *next;
+	int ret, err = 0;
 
+	mutex_lock(&mtd_partitions_mutex);
 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 		if (slave->master == master) {
+			ret = del_mtd_device(&slave->mtd);
+			if (ret < 0) {
+				err = ret;
+				continue;
+			}
 			list_del(&slave->list);
-			if (slave->registered)
-				del_mtd_device(&slave->mtd);
-			kfree(slave);
+			free_partition(slave);
 		}
+	mutex_unlock(&mtd_partitions_mutex);
 
-	return 0;
+	return err;
 }
 
-static struct mtd_part *add_one_partition(struct mtd_info *master,
-		const struct mtd_partition *part, int partno,
-		uint64_t cur_offset)
+static struct mtd_part *allocate_partition(struct mtd_info *master,
+			const struct mtd_partition *part, int partno,
+			uint64_t cur_offset)
 {
 	struct mtd_part *slave;
+	char *name;
 
 	/* allocate the partition structure */
 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
-	if (!slave) {
+	name = kstrdup(part->name, GFP_KERNEL);
+	if (!name || !slave) {
 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
-			master->name);
-		del_mtd_partitions(master);
-		return NULL;
+		       master->name);
+		kfree(name);
+		kfree(slave);
+		return ERR_PTR(-ENOMEM);
 	}
-	list_add(&slave->list, &mtd_partitions);
 
 	/* set up the MTD object for this partition */
 	slave->mtd.type = master->type;
 	slave->mtd.flags = master->flags & ~part->mask_flags;
 	slave->mtd.size = part->size;
 	slave->mtd.writesize = master->writesize;
+	slave->mtd.writebufsize = master->writebufsize;
 	slave->mtd.oobsize = master->oobsize;
 	slave->mtd.oobavail = master->oobavail;
 	slave->mtd.subpage_sft = master->subpage_sft;
 
-	slave->mtd.name = part->name;
+	slave->mtd.name = name;
 	slave->mtd.owner = master->owner;
+#ifndef __UBOOT__
+	slave->mtd.backing_dev_info = master->backing_dev_info;
+
+	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
+	 * to have the same data be in two different partitions.
+	 */
+	slave->mtd.dev.parent = master->dev.parent;
+#endif
 
 	slave->mtd._read = part_read;
 	slave->mtd._write = part_write;
 
+	if (master->_panic_write)
+		slave->mtd._panic_write = part_panic_write;
+
+#ifndef __UBOOT__
+	if (master->_point && master->_unpoint) {
+		slave->mtd._point = part_point;
+		slave->mtd._unpoint = part_unpoint;
+	}
+#endif
+
+	if (master->_get_unmapped_area)
+		slave->mtd._get_unmapped_area = part_get_unmapped_area;
 	if (master->_read_oob)
 		slave->mtd._read_oob = part_read_oob;
 	if (master->_write_oob)
@@ -278,10 +443,21 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 		slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 	if (master->_sync)
 		slave->mtd._sync = part_sync;
+#ifndef __UBOOT__
+	if (!partno && !master->dev.class && master->_suspend &&
+	    master->_resume) {
+			slave->mtd._suspend = part_suspend;
+			slave->mtd._resume = part_resume;
+	}
+	if (master->_writev)
+		slave->mtd._writev = part_writev;
+#endif
 	if (master->_lock)
 		slave->mtd._lock = part_lock;
 	if (master->_unlock)
 		slave->mtd._unlock = part_unlock;
+	if (master->_is_locked)
+		slave->mtd._is_locked = part_is_locked;
 	if (master->_block_isbad)
 		slave->mtd._block_isbad = part_block_isbad;
 	if (master->_block_markbad)
@@ -289,7 +465,6 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 	slave->mtd._erase = part_erase;
 	slave->master = master;
 	slave->offset = part->offset;
-	slave->index = partno;
 
 	if (slave->offset == MTDPART_OFS_APPEND)
 		slave->offset = cur_offset;
@@ -298,18 +473,29 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 		if (mtd_mod_by_eb(cur_offset, master) != 0) {
 			/* Round up to next erasesize */
 			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
-			debug("Moving partition %d: 0x%012llx -> 0x%012llx\n",
-			      partno, (unsigned long long)cur_offset,
-			      (unsigned long long)slave->offset);
+			debug("Moving partition %d: "
+			       "0x%012llx -> 0x%012llx\n", partno,
+			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
+		}
+	}
+	if (slave->offset == MTDPART_OFS_RETAIN) {
+		slave->offset = cur_offset;
+		if (master->size - slave->offset >= slave->mtd.size) {
+			slave->mtd.size = master->size - slave->offset
+							- slave->mtd.size;
+		} else {
+			debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
+				part->name, master->size - slave->offset,
+				slave->mtd.size);
+			/* register to preserve ordering */
+			goto out_register;
 		}
 	}
 	if (slave->mtd.size == MTDPART_SIZ_FULL)
 		slave->mtd.size = master->size - slave->offset;
 
-	debug("0x%012llx-0x%012llx : \"%s\"\n",
-	      (unsigned long long)slave->offset,
-	      (unsigned long long)(slave->offset + slave->mtd.size),
-	      slave->mtd.name);
+	debug("0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
+		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 
 	/* let's do some sanity checks */
 	if (slave->offset >= master->size) {
@@ -336,7 +522,8 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 			;
 		/* The loop searched for the region _behind_ the first one */
-		i--;
+		if (i > 0)
+			i--;
 
 		/* Pick biggest erasesize */
 		for (; i < max && regions[i].offset < end; i++) {
@@ -367,6 +554,10 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 	}
 
 	slave->mtd.ecclayout = master->ecclayout;
+	slave->mtd.ecc_step_size = master->ecc_step_size;
+	slave->mtd.ecc_strength = master->ecc_strength;
+	slave->mtd.bitflip_threshold = master->bitflip_threshold;
+
 	if (master->_block_isbad) {
 		uint64_t offs = 0;
 
@@ -378,18 +569,89 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 	}
 
 out_register:
-	if (part->mtdp) {
-		/* store the object pointer (caller may or may not register it*/
-		*part->mtdp = &slave->mtd;
-		slave->registered = 0;
-	} else {
-		/* register our partition */
-		add_mtd_device(&slave->mtd);
-		slave->registered = 1;
-	}
 	return slave;
 }
 
+int mtd_add_partition(struct mtd_info *master, const char *name,
+		      long long offset, long long length)
+{
+	struct mtd_partition part;
+	struct mtd_part *p, *new;
+	uint64_t start, end;
+	int ret = 0;
+
+	/* the direct offset is expected */
+	if (offset == MTDPART_OFS_APPEND ||
+	    offset == MTDPART_OFS_NXTBLK)
+		return -EINVAL;
+
+	if (length == MTDPART_SIZ_FULL)
+		length = master->size - offset;
+
+	if (length <= 0)
+		return -EINVAL;
+
+	part.name = name;
+	part.size = length;
+	part.offset = offset;
+	part.mask_flags = 0;
+	part.ecclayout = NULL;
+
+	new = allocate_partition(master, &part, -1, offset);
+	if (IS_ERR(new))
+		return PTR_ERR(new);
+
+	start = offset;
+	end = offset + length;
+
+	mutex_lock(&mtd_partitions_mutex);
+	list_for_each_entry(p, &mtd_partitions, list)
+		if (p->master == master) {
+			if ((start >= p->offset) &&
+			    (start < (p->offset + p->mtd.size)))
+				goto err_inv;
+
+			if ((end >= p->offset) &&
+			    (end < (p->offset + p->mtd.size)))
+				goto err_inv;
+		}
+
+	list_add(&new->list, &mtd_partitions);
+	mutex_unlock(&mtd_partitions_mutex);
+
+	add_mtd_device(&new->mtd);
+
+	return ret;
+err_inv:
+	mutex_unlock(&mtd_partitions_mutex);
+	free_partition(new);
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(mtd_add_partition);
+
+int mtd_del_partition(struct mtd_info *master, int partno)
+{
+	struct mtd_part *slave, *next;
+	int ret = -EINVAL;
+
+	mutex_lock(&mtd_partitions_mutex);
+	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
+		if ((slave->master == master) &&
+		    (slave->mtd.index == partno)) {
+			ret = del_mtd_device(&slave->mtd);
+			if (ret < 0)
+				break;
+
+			list_del(&slave->list);
+			free_partition(slave);
+			break;
+		}
+	mutex_unlock(&mtd_partitions_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mtd_del_partition);
+
 /*
  * This function, given a master MTD object and a partition table, creates
  * and registers slave MTD objects which are bound to the master according to
@@ -407,6 +669,7 @@ int add_mtd_partitions(struct mtd_info *master,
 	uint64_t cur_offset = 0;
 	int i;
 
+#ifdef __UBOOT__
 	/*
 	 * Need to init the list here, since LIST_INIT() does not
 	 * work on platforms where relocation has problems (like MIPS
@@ -414,15 +677,147 @@ int add_mtd_partitions(struct mtd_info *master,
 	 */
 	if (mtd_partitions.next == NULL)
 		INIT_LIST_HEAD(&mtd_partitions);
+#endif
 
 	debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 
 	for (i = 0; i < nbparts; i++) {
-		slave = add_one_partition(master, parts + i, i, cur_offset);
-		if (!slave)
-			return -ENOMEM;
+		slave = allocate_partition(master, parts + i, i, cur_offset);
+		if (IS_ERR(slave))
+			return PTR_ERR(slave);
+
+		mutex_lock(&mtd_partitions_mutex);
+		list_add(&slave->list, &mtd_partitions);
+		mutex_unlock(&mtd_partitions_mutex);
+
+		add_mtd_device(&slave->mtd);
+
 		cur_offset = slave->offset + slave->mtd.size;
 	}
 
 	return 0;
 }
+
+#ifndef __UBOOT__
+static DEFINE_SPINLOCK(part_parser_lock);
+static LIST_HEAD(part_parsers);
+
+static struct mtd_part_parser *get_partition_parser(const char *name)
+{
+	struct mtd_part_parser *p, *ret = NULL;
+
+	spin_lock(&part_parser_lock);
+
+	list_for_each_entry(p, &part_parsers, list)
+		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
+			ret = p;
+			break;
+		}
+
+	spin_unlock(&part_parser_lock);
+
+	return ret;
+}
+
+#define put_partition_parser(p) do { module_put((p)->owner); } while (0)
+
+void register_mtd_parser(struct mtd_part_parser *p)
+{
+	spin_lock(&part_parser_lock);
+	list_add(&p->list, &part_parsers);
+	spin_unlock(&part_parser_lock);
+}
+EXPORT_SYMBOL_GPL(register_mtd_parser);
+
+void deregister_mtd_parser(struct mtd_part_parser *p)
+{
+	spin_lock(&part_parser_lock);
+	list_del(&p->list);
+	spin_unlock(&part_parser_lock);
+}
+EXPORT_SYMBOL_GPL(deregister_mtd_parser);
+
+/*
+ * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
+ * are changing this array!
+ */
+static const char * const default_mtd_part_types[] = {
+	"cmdlinepart",
+	"ofpart",
+	NULL
+};
+
+/**
+ * parse_mtd_partitions - parse MTD partitions
+ * @master: the master partition (describes whole MTD device)
+ * @types: names of partition parsers to try or %NULL
+ * @pparts: array of partitions found is returned here
+ * @data: MTD partition parser-specific data
+ *
+ * This function tries to find partition on MTD device @master. It uses MTD
+ * partition parsers, specified in @types. However, if @types is %NULL, then
+ * the default list of parsers is used. The default list contains only the
+ * "cmdlinepart" and "ofpart" parsers ATM.
+ * Note: If there are more then one parser in @types, the kernel only takes the
+ * partitions parsed out by the first parser.
+ *
+ * This function may return:
+ * o a negative error code in case of failure
+ * o zero if no partitions were found
+ * o a positive number of found partitions, in which case on exit @pparts will
+ *   point to an array containing this number of &struct mtd_info objects.
+ */
+int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
+			 struct mtd_partition **pparts,
+			 struct mtd_part_parser_data *data)
+{
+	struct mtd_part_parser *parser;
+	int ret = 0;
+
+	if (!types)
+		types = default_mtd_part_types;
+
+	for ( ; ret <= 0 && *types; types++) {
+		parser = get_partition_parser(*types);
+		if (!parser && !request_module("%s", *types))
+			parser = get_partition_parser(*types);
+		if (!parser)
+			continue;
+		ret = (*parser->parse_fn)(master, pparts, data);
+		put_partition_parser(parser);
+		if (ret > 0) {
+			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
+			       ret, parser->name, master->name);
+			break;
+		}
+	}
+	return ret;
+}
+#endif
+
+int mtd_is_partition(const struct mtd_info *mtd)
+{
+	struct mtd_part *part;
+	int ispart = 0;
+
+	mutex_lock(&mtd_partitions_mutex);
+	list_for_each_entry(part, &mtd_partitions, list)
+		if (&part->mtd == mtd) {
+			ispart = 1;
+			break;
+		}
+	mutex_unlock(&mtd_partitions_mutex);
+
+	return ispart;
+}
+EXPORT_SYMBOL_GPL(mtd_is_partition);
+
+/* Returns the size of the entire flash chip */
+uint64_t mtd_get_device_size(const struct mtd_info *mtd)
+{
+	if (!mtd_is_partition(mtd))
+		return mtd->size;
+
+	return PART(mtd)->master->size;
+}
+EXPORT_SYMBOL_GPL(mtd_get_device_size);